Opening a Store in the states

hi i stumbled across this website and i was wondering what type of citizenship would i need to open a store in California and live there for about 4-6 month of the year

Citizenship doesn't matter, what does matter is a work permit or some sort of visa that allows you to work.

but most of the visa and work permits talk about working for an employer what would i need if i was the employer

Look for information on an investor visa, or something like that. I'm sorry, I really don't know much about it.

Why not just keep your money in Canada and open a store there?

You most likely want to look at the E visa (investor visa).

Here's a brief overview:
http://www.tnvisaexpert.com/resources/other_options/

You'll want to speak to a lawyer - proper documentation, the investment requirement, etc. will be required when applying for this type of visa.

Get an E-2 visa. All E-2s are processed in Toronto. Good luck.